1. Field of the Invention
This invention relates generally to processor architecture and more particularly to information exchange between multiple processors sharing memory.
2. Description of the Related Art
Missions critical systems for enterprises require a design that emphasizes reliability. For example, for a high-end/mission critical system where there is only one instance of key components, failure of one of the key components will bring down the entire system. This would have drastic results for the owner of the system, irrespective of the applications executed by the system. Some exemplary applications requiring reliability include electronic commerce applications and commercial database applications, etc.
One attempt to address this shortcoming for mission critical systems is to provide redundant fabric which operates on a standby basis. FIG. 1 is a simplified schematic of the architecture for redundant fabric configured to operate on a standby basis. Switch 100 connects multiple central processing units (CPU) 102a-102n. Each of the multiple central processing units (CPU) 102a-102n are associated with one of memories 104a-104n. Switch fabric 100 is configured to allow any one of CPUs 102a-102n to access any of memories 104a-104n. A second instance of the key components is provided through redundant fabric illustrated by switch 100′, CPUs 102a′-102n′ and memories 104a′-104n′. However, this 100% redundancy through replication becomes expensive and requires significantly more overhead because the state of the system is being duplicated. That is, the costs for one system is being duplicated for a standby system.
In view of the forgoing, there is a need define a communication system within a multi-chip processor that allows the multiple processors to exchange information through horizontal scaling without using shared memory.